compress.c revision 58630 
1/*-
2 * Copyright (c) 1992, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 *    must display the following acknowledgement:
15 *	This product includes software developed by the University of
16 *	California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#ifndef lint
35static const char copyright[] =
36"@(#) Copyright (c) 1992, 1993\n\
37	The Regents of the University of California.  All rights reserved.\n";
38#endif /* not lint */
39
40#ifndef lint
41#if 0
42static char sccsid[] = "@(#)compress.c	8.2 (Berkeley) 1/7/94";
43#endif
44static const char rcsid[] =
45  "$FreeBSD: head/usr.bin/compress/compress.c 58630 2000-03-26 15:10:37Z charnier $";
46#endif /* not lint */
47
48#include <sys/param.h>
49#include <sys/stat.h>
50
51#include <err.h>
52#include <errno.h>
53#include <stdio.h>
54#include <stdlib.h>
55#include <string.h>
56#include <unistd.h>
57
58#ifdef __STDC__
59#include <stdarg.h>
60#else
61#include <varargs.h>
62#endif
63
64#include "zopen.h"
65
66void	compress __P((char *, char *, int));
67void	cwarn __P((const char *, ...));
68void	cwarnx __P((const char *, ...));
69void	decompress __P((char *, char *, int));
70int	permission __P((char *));
71void	setfile __P((char *, struct stat *));
72void	usage __P((int));
73
74int eval, force, verbose;
75
76int
77main(argc, argv)
78	int argc;
79	char *argv[];
80{
81	enum {COMPRESS, DECOMPRESS} style;
82	size_t len;
83	int bits, cat, ch;
84	char *p, newname[MAXPATHLEN];
85
86	cat = 0;
87	if ((p = rindex(argv[0], '/')) == NULL)
88		p = argv[0];
89	else
90		++p;
91	if (!strcmp(p, "uncompress"))
92		style = DECOMPRESS;
93	else if (!strcmp(p, "compress"))
94		style = COMPRESS;
95	else if (!strcmp(p, "zcat")) {
96		cat = 1;
97		style = DECOMPRESS;
98	} else
99		errx(1, "unknown program name");
100
101	bits = 0;
102	while ((ch = getopt(argc, argv, "b:cdfv")) != -1)
103		switch(ch) {
104		case 'b':
105			bits = strtol(optarg, &p, 10);
106			if (*p)
107				errx(1, "illegal bit count -- %s", optarg);
108			break;
109		case 'c':
110			cat = 1;
111			break;
112		case 'd':		/* Backward compatible. */
113			style = DECOMPRESS;
114			break;
115		case 'f':
116			force = 1;
117			break;
118		case 'v':
119			verbose = 1;
120			break;
121		case '?':
122		default:
123			usage(style == COMPRESS);
124		}
125	argc -= optind;
126	argv += optind;
127
128	if (argc == 0) {
129		switch(style) {
130		case COMPRESS:
131			(void)compress("/dev/stdin", "/dev/stdout", bits);
132			break;
133		case DECOMPRESS:
134			(void)decompress("/dev/stdin", "/dev/stdout", bits);
135			break;
136		}
137		exit (eval);
138	}
139
140	if (cat == 1 && argc > 1)
141		errx(1, "the -c option permits only a single file argument");
142
143	for (; *argv; ++argv)
144		switch(style) {
145		case COMPRESS:
146			if (cat) {
147				compress(*argv, "/dev/stdout", bits);
148				break;
149			}
150			if ((p = rindex(*argv, '.')) != NULL &&
151			    !strcmp(p, ".Z")) {
152				cwarnx("%s: name already has trailing .Z",
153				    *argv);
154				break;
155			}
156			len = strlen(*argv);
157			if (len > sizeof(newname) - 3) {
158				cwarnx("%s: name too long", *argv);
159				break;
160			}
161			memmove(newname, *argv, len);
162			newname[len] = '.';
163			newname[len + 1] = 'Z';
164			newname[len + 2] = '\0';
165			compress(*argv, newname, bits);
166			break;
167		case DECOMPRESS:
168			len = strlen(*argv);
169			if ((p = rindex(*argv, '.')) == NULL ||
170			    strcmp(p, ".Z")) {
171				if (len > sizeof(newname) - 3) {
172					cwarnx("%s: name too long", *argv);
173					break;
174				}
175				memmove(newname, *argv, len);
176				newname[len] = '.';
177				newname[len + 1] = 'Z';
178				newname[len + 2] = '\0';
179				decompress(newname,
180				    cat ? "/dev/stdout" : *argv, bits);
181			} else {
182				if (len - 2 > sizeof(newname) - 1) {
183					cwarnx("%s: name too long", *argv);
184					break;
185				}
186				memmove(newname, *argv, len - 2);
187				newname[len - 2] = '\0';
188				decompress(*argv,
189				    cat ? "/dev/stdout" : newname, bits);
190			}
191			break;
192		}
193	exit (eval);
194}
195
196void
197compress(in, out, bits)
198	char *in, *out;
199	int bits;
200{
201	register int nr;
202	struct stat isb, sb;
203	FILE *ifp, *ofp;
204	int exists, isreg, oreg;
205	u_char buf[1024];
206
207	exists = !stat(out, &sb);
208	if (!force && exists && S_ISREG(sb.st_mode) && !permission(out))
209		return;
210	isreg = oreg = !exists || S_ISREG(sb.st_mode);
211
212	ifp = ofp = NULL;
213	if ((ifp = fopen(in, "r")) == NULL) {
214		cwarn("%s", in);
215		return;
216	}
217	if (stat(in, &isb)) {		/* DON'T FSTAT! */
218		cwarn("%s", in);
219		goto err;
220	}
221	if (!S_ISREG(isb.st_mode))
222		isreg = 0;
223
224	if ((ofp = zopen(out, "w", bits)) == NULL) {
225		cwarn("%s", out);
226		goto err;
227	}
228	while ((nr = fread(buf, 1, sizeof(buf), ifp)) != 0)
229		if (fwrite(buf, 1, nr, ofp) != nr) {
230			cwarn("%s", out);
231			goto err;
232		}
233
234	if (ferror(ifp) || fclose(ifp)) {
235		cwarn("%s", in);
236		goto err;
237	}
238	ifp = NULL;
239
240	if (fclose(ofp)) {
241		cwarn("%s", out);
242		goto err;
243	}
244	ofp = NULL;
245
246	if (isreg) {
247		if (stat(out, &sb)) {
248			cwarn("%s", out);
249			goto err;
250		}
251
252		if (!force && sb.st_size >= isb.st_size) {
253			if (verbose)
254		(void)printf("%s: file would grow; left unmodified\n", in);
255			if (unlink(out))
256				cwarn("%s", out);
257			goto err;
258		}
259
260		setfile(out, &isb);
261
262		if (unlink(in))
263			cwarn("%s", in);
264
265		if (verbose) {
266			(void)printf("%s: ", out);
267			if (isb.st_size > sb.st_size)
268				(void)printf("%.0f%% compression\n",
269				    ((float)sb.st_size / isb.st_size) * 100.0);
270			else
271				(void)printf("%.0f%% expansion\n",
272				    ((float)isb.st_size / sb.st_size) * 100.0);
273		}
274	}
275	return;
276
277err:	if (ofp) {
278		if (oreg)
279			(void)unlink(out);
280		(void)fclose(ofp);
281	}
282	if (ifp)
283		(void)fclose(ifp);
284}
285
286void
287decompress(in, out, bits)
288	char *in, *out;
289	int bits;
290{
291	register int nr;
292	struct stat sb;
293	FILE *ifp, *ofp;
294	int exists, isreg, oreg;
295	u_char buf[1024];
296
297	exists = !stat(out, &sb);
298	if (!force && exists && S_ISREG(sb.st_mode) && !permission(out))
299		return;
300	isreg = oreg = !exists || S_ISREG(sb.st_mode);
301
302	ifp = ofp = NULL;
303	if ((ofp = fopen(out, "w")) == NULL) {
304		cwarn("%s", out);
305		return;
306	}
307
308	if ((ifp = zopen(in, "r", bits)) == NULL) {
309		cwarn("%s", in);
310		goto err;
311	}
312	if (stat(in, &sb)) {
313		cwarn("%s", in);
314		goto err;
315	}
316	if (!S_ISREG(sb.st_mode))
317		isreg = 0;
318
319	while ((nr = fread(buf, 1, sizeof(buf), ifp)) != 0)
320		if (fwrite(buf, 1, nr, ofp) != nr) {
321			cwarn("%s", out);
322			goto err;
323		}
324
325	if (ferror(ifp) || fclose(ifp)) {
326		cwarn("%s", in);
327		goto err;
328	}
329	ifp = NULL;
330
331	if (fclose(ofp)) {
332		cwarn("%s", out);
333		goto err;
334	}
335
336	if (isreg) {
337		setfile(out, &sb);
338
339		if (unlink(in))
340			cwarn("%s", in);
341	}
342	return;
343
344err:	if (ofp) {
345		if (oreg)
346			(void)unlink(out);
347		(void)fclose(ofp);
348	}
349	if (ifp)
350		(void)fclose(ifp);
351}
352
353void
354setfile(name, fs)
355	char *name;
356	register struct stat *fs;
357{
358	static struct timeval tv[2];
359
360	fs->st_mode &= S_ISUID|S_ISGID|S_IRWXU|S_IRWXG|S_IRWXO;
361
362	TIMESPEC_TO_TIMEVAL(&tv[0], &fs->st_atimespec);
363	TIMESPEC_TO_TIMEVAL(&tv[1], &fs->st_mtimespec);
364	if (utimes(name, tv))
365		cwarn("utimes: %s", name);
366
367	/*
368	 * Changing the ownership probably won't succeed, unless we're root
369	 * or POSIX_CHOWN_RESTRICTED is not set.  Set uid/gid before setting
370	 * the mode; current BSD behavior is to remove all setuid bits on
371	 * chown.  If chown fails, lose setuid/setgid bits.
372	 */
373	if (chown(name, fs->st_uid, fs->st_gid)) {
374		if (errno != EPERM)
375			cwarn("chown: %s", name);
376		fs->st_mode &= ~(S_ISUID|S_ISGID);
377	}
378	if (chmod(name, fs->st_mode))
379		cwarn("chmod: %s", name);
380
381	if (chflags(name, fs->st_flags))
382		cwarn("chflags: %s", name);
383}
384
385int
386permission(fname)
387	char *fname;
388{
389	int ch, first;
390
391	if (!isatty(fileno(stderr)))
392		return (0);
393	(void)fprintf(stderr, "overwrite %s? ", fname);
394	first = ch = getchar();
395	while (ch != '\n' && ch != EOF)
396		ch = getchar();
397	return (first == 'y');
398}
399
400void
401usage(iscompress)
402	int iscompress;
403{
404	if (iscompress)
405		(void)fprintf(stderr,
406		    "usage: compress [-cfv] [-b bits] [file ...]\n");
407	else
408		(void)fprintf(stderr,
409		    "usage: uncompress [-c] [-b bits] [file ...]\n");
410	exit(1);
411}
412
413void
414#if __STDC__
415cwarnx(const char *fmt, ...)
416#else
417cwarnx(fmt, va_alist)
418	int eval;
419	const char *fmt;
420	va_dcl
421#endif
422{
423	va_list ap;
424#if __STDC__
425	va_start(ap, fmt);
426#else
427	va_start(ap);
428#endif
429	vwarnx(fmt, ap);
430	va_end(ap);
431	eval = 1;
432}
433
434void
435#if __STDC__
436cwarn(const char *fmt, ...)
437#else
438cwarn(fmt, va_alist)
439	int eval;
440	const char *fmt;
441	va_dcl
442#endif
443{
444	va_list ap;
445#if __STDC__
446	va_start(ap, fmt);
447#else
448	va_start(ap);
449#endif
450	vwarn(fmt, ap);
451	va_end(ap);
452	eval = 1;
453}
454